There goes another one. At least this time I kind of know why he died. Bloatedness for some reason. I really have no clue how that happened though. My update has more details...
For those who didn't see...I believe it had pop-eye or dropsy (thanks to helena who pointed that out ). Don't really know how that happened. I did an 80% wc and will hope it goes well. I did find some white worm things in the tank. After cleaning they were gone. Maybe that was the problem...? I don't see any of the other cories acting weird so hopefully I won't have many more casualties in the near future!